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24 | </div> | |
25 | <div class="section boost_bimap_the_tutorial_the_collection_of_relations_type"> | |
26 | <div class="titlepage"><div><div><h3 class="title"> | |
27 | <a name="boost_bimap.the_tutorial.the_collection_of_relations_type"></a><a class="link" href="the_collection_of_relations_type.html" title="The collection of relations type">The | |
28 | collection of relations type</a> | |
29 | </h3></div></div></div> | |
30 | <div class="toc"><dl> | |
31 | <dt><span class="section"><a href="the_collection_of_relations_type.html#boost_bimap.the_tutorial.the_collection_of_relations_type.a_new_point_of_view">A | |
32 | new point of view</a></span></dt> | |
33 | <dt><span class="section"><a href="the_collection_of_relations_type.html#boost_bimap.the_tutorial.the_collection_of_relations_type.configuration_parameters">Configuration | |
34 | parameters</a></span></dt> | |
35 | <dt><span class="section"><a href="the_collection_of_relations_type.html#boost_bimap.the_tutorial.the_collection_of_relations_type.examples">Examples</a></span></dt> | |
36 | </dl></div> | |
37 | <div class="section boost_bimap_the_tutorial_the_collection_of_relations_type_a_new_point_of_view"> | |
38 | <div class="titlepage"><div><div><h4 class="title"> | |
39 | <a name="boost_bimap.the_tutorial.the_collection_of_relations_type.a_new_point_of_view"></a><a class="link" href="the_collection_of_relations_type.html#boost_bimap.the_tutorial.the_collection_of_relations_type.a_new_point_of_view" title="A new point of view">A | |
40 | new point of view</a> | |
41 | </h4></div></div></div> | |
42 | <p> | |
43 | Being able to change the collection type of the bimap relation view is | |
44 | another very important feature. Remember that this view allows the user | |
45 | to see the container as a group of the stored relations. This view has | |
46 | set semantics instead of map semantics. | |
47 | </p> | |
48 | <p> | |
49 | <span class="inlinemediaobject"><img src="../../images/bimap/collection.type.of.relation.png" alt="collection.type.of.relation"></span> | |
50 | </p> | |
51 | <p> | |
52 | By default, Boost.Bimap will base the collection type of the relation on | |
53 | the type of the left collection. If the left collection type is a set, | |
54 | then the collection type of the relation will be a set with the same order | |
55 | as the left view. | |
56 | </p> | |
57 | <p> | |
58 | In general, Boost.Bimap users will base the collection type of a relation | |
59 | on the type of the collection on one of the two sides. However there are | |
60 | times where it is useful to give this collection other constraints or simply | |
61 | to order it differently. The user is allowed to choose between: | |
62 | </p> | |
63 | <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> | |
64 | <li class="listitem"> | |
65 | left_based | |
66 | </li> | |
67 | <li class="listitem"> | |
68 | right_based | |
69 | </li> | |
70 | <li class="listitem"> | |
71 | set_of_relation<> | |
72 | </li> | |
73 | <li class="listitem"> | |
74 | multiset_of_relation<> | |
75 | </li> | |
76 | <li class="listitem"> | |
77 | unordered_set_of_relation<> | |
78 | </li> | |
79 | <li class="listitem"> | |
80 | unordered_multiset_of_relation<> | |
81 | </li> | |
82 | <li class="listitem"> | |
83 | list_of_relation | |
84 | </li> | |
85 | <li class="listitem"> | |
86 | vector_of_relation | |
87 | </li> | |
88 | <li class="listitem"> | |
89 | unconstrained_set_of_relation | |
90 | </li> | |
91 | </ul></div> | |
92 | <div class="tip"><table border="0" summary="Tip"> | |
93 | <tr> | |
94 | <td rowspan="2" align="center" valign="top" width="25"><img alt="[Tip]" src="../../../../../../doc/src/images/tip.png"></td> | |
95 | <th align="left">Tip</th> | |
96 | </tr> | |
97 | <tr><td align="left" valign="top"><p> | |
98 | The first two options and the last produce faster bimaps, so prefer these | |
99 | where possible. | |
100 | </p></td></tr> | |
101 | </table></div> | |
102 | <p> | |
103 | <span class="inlinemediaobject"><img src="../../images/bimap/more.bimap.structures.png" alt="more.bimap.structures"></span> | |
104 | </p> | |
105 | <p> | |
106 | The collection type of relation can be used to create powerful containers. | |
107 | For example, if you need to maximize search speed, then the best bidirectional | |
108 | map possible is one that relates elements from an <code class="computeroutput"><span class="identifier">unordered_set</span></code> | |
109 | to another <code class="computeroutput"><span class="identifier">unordered_set</span></code>. | |
110 | The problem is that this container cannot be iterated. If you need to know | |
111 | the list of relations inside the container, you need another collection | |
112 | type of relation. In this case, a <code class="computeroutput"><span class="identifier">list_of_relation</span></code> | |
113 | is a good choice. The resulting container trades insertion and deletion | |
114 | time against fast search capabilities and the possibility of bidirectional | |
115 | iteration. | |
116 | </p> | |
117 | <p> | |
118 | <a href="../../../../example/mighty_bimap.cpp" target="_top">Go to source code</a> | |
119 | </p> | |
120 | <p> | |
121 | </p> | |
122 | <pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">iostream</span><span class="special">></span> | |
123 | <span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">string</span><span class="special">></span> | |
124 | <span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">bimap</span><span class="special">/</span><span class="identifier">bimap</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> | |
125 | <span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">bimap</span><span class="special">/</span><span class="identifier">list_of</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> | |
126 | <span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">bimap</span><span class="special">/</span><span class="identifier">unordered_set_of</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> | |
127 | ||
128 | <span class="keyword">struct</span> <span class="identifier">english</span> <span class="special">{};</span> | |
129 | <span class="keyword">struct</span> <span class="identifier">spanish</span> <span class="special">{};</span> | |
130 | ||
131 | <span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span> | |
132 | <span class="special">{</span> | |
133 | <span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">bimaps</span><span class="special">;</span> | |
134 | ||
135 | <span class="keyword">typedef</span> <span class="identifier">bimap</span> | |
136 | <span class="special"><</span> | |
137 | <span class="identifier">unordered_set_of</span><span class="special"><</span> <span class="identifier">tagged</span><span class="special"><</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">,</span> <span class="identifier">spanish</span> <span class="special">></span> <span class="special">>,</span> | |
138 | <span class="identifier">unordered_set_of</span><span class="special"><</span> <span class="identifier">tagged</span><span class="special"><</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">,</span> <span class="identifier">english</span> <span class="special">></span> <span class="special">>,</span> | |
139 | <span class="identifier">list_of_relation</span> | |
140 | ||
141 | <span class="special">></span> <span class="identifier">translator</span><span class="special">;</span> | |
142 | ||
143 | <span class="identifier">translator</span> <span class="identifier">trans</span><span class="special">;</span> | |
144 | ||
145 | <span class="comment">// We have to use `push_back` because the collection of relations is</span> | |
146 | <span class="comment">// a `list_of_relation`</span> | |
147 | ||
148 | <span class="identifier">trans</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span> <span class="identifier">translator</span><span class="special">::</span><span class="identifier">value_type</span><span class="special">(</span><span class="string">"hola"</span> <span class="special">,</span><span class="string">"hello"</span> <span class="special">)</span> <span class="special">);</span> | |
149 | <span class="identifier">trans</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span> <span class="identifier">translator</span><span class="special">::</span><span class="identifier">value_type</span><span class="special">(</span><span class="string">"adios"</span> <span class="special">,</span><span class="string">"goodbye"</span> <span class="special">)</span> <span class="special">);</span> | |
150 | <span class="identifier">trans</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span> <span class="identifier">translator</span><span class="special">::</span><span class="identifier">value_type</span><span class="special">(</span><span class="string">"rosa"</span> <span class="special">,</span><span class="string">"rose"</span> <span class="special">)</span> <span class="special">);</span> | |
151 | <span class="identifier">trans</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span> <span class="identifier">translator</span><span class="special">::</span><span class="identifier">value_type</span><span class="special">(</span><span class="string">"mesa"</span> <span class="special">,</span><span class="string">"table"</span> <span class="special">)</span> <span class="special">);</span> | |
152 | ||
153 | <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"enter a word"</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> | |
154 | <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">word</span><span class="special">;</span> | |
155 | <span class="identifier">std</span><span class="special">::</span><span class="identifier">getline</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">cin</span><span class="special">,</span><span class="identifier">word</span><span class="special">);</span> | |
156 | ||
157 | <span class="comment">// Search the queried word on the from index (Spanish)</span> | |
158 | ||
159 | <span class="identifier">translator</span><span class="special">::</span><span class="identifier">map_by</span><span class="special"><</span><span class="identifier">spanish</span><span class="special">>::</span><span class="identifier">const_iterator</span> <span class="identifier">is</span> | |
160 | <span class="special">=</span> <span class="identifier">trans</span><span class="special">.</span><span class="identifier">by</span><span class="special"><</span><span class="identifier">spanish</span><span class="special">>().</span><span class="identifier">find</span><span class="special">(</span><span class="identifier">word</span><span class="special">);</span> | |
161 | ||
162 | <span class="keyword">if</span><span class="special">(</span> <span class="identifier">is</span> <span class="special">!=</span> <span class="identifier">trans</span><span class="special">.</span><span class="identifier">by</span><span class="special"><</span><span class="identifier">spanish</span><span class="special">>().</span><span class="identifier">end</span><span class="special">()</span> <span class="special">)</span> | |
163 | <span class="special">{</span> | |
164 | <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="identifier">word</span> <span class="special"><<</span> <span class="string">" is said "</span> | |
165 | <span class="special"><<</span> <span class="identifier">is</span><span class="special">-></span><span class="identifier">get</span><span class="special"><</span><span class="identifier">english</span><span class="special">>()</span> | |
166 | <span class="special"><<</span> <span class="string">" in English"</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> | |
167 | <span class="special">}</span> | |
168 | <span class="keyword">else</span> | |
169 | <span class="special">{</span> | |
170 | <span class="comment">// Word not found in Spanish, try our luck in English</span> | |
171 | ||
172 | <span class="identifier">translator</span><span class="special">::</span><span class="identifier">map_by</span><span class="special"><</span><span class="identifier">english</span><span class="special">>::</span><span class="identifier">const_iterator</span> <span class="identifier">ie</span> | |
173 | <span class="special">=</span> <span class="identifier">trans</span><span class="special">.</span><span class="identifier">by</span><span class="special"><</span><span class="identifier">english</span><span class="special">>().</span><span class="identifier">find</span><span class="special">(</span><span class="identifier">word</span><span class="special">);</span> | |
174 | ||
175 | <span class="keyword">if</span><span class="special">(</span> <span class="identifier">ie</span> <span class="special">!=</span> <span class="identifier">trans</span><span class="special">.</span><span class="identifier">by</span><span class="special"><</span><span class="identifier">english</span><span class="special">>().</span><span class="identifier">end</span><span class="special">()</span> <span class="special">)</span> | |
176 | <span class="special">{</span> | |
177 | <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="identifier">word</span> <span class="special"><<</span> <span class="string">" is said "</span> | |
178 | <span class="special"><<</span> <span class="identifier">ie</span><span class="special">-></span><span class="identifier">get</span><span class="special"><</span><span class="identifier">spanish</span><span class="special">>()</span> | |
179 | <span class="special"><<</span> <span class="string">" in Spanish"</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> | |
180 | <span class="special">}</span> | |
181 | <span class="keyword">else</span> | |
182 | <span class="special">{</span> | |
183 | <span class="comment">// Word not found, show the possible translations</span> | |
184 | ||
185 | <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"No such word in the dictionary"</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> | |
186 | <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"These are the possible translations"</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> | |
187 | ||
188 | <span class="keyword">for</span><span class="special">(</span> <span class="identifier">translator</span><span class="special">::</span><span class="identifier">const_iterator</span> | |
189 | <span class="identifier">i</span> <span class="special">=</span> <span class="identifier">trans</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span> | |
190 | <span class="identifier">i_end</span> <span class="special">=</span> <span class="identifier">trans</span><span class="special">.</span><span class="identifier">end</span><span class="special">();</span> | |
191 | ||
192 | <span class="identifier">i</span> <span class="special">!=</span> <span class="identifier">i_end</span> <span class="special">;</span> <span class="special">++</span><span class="identifier">i</span> <span class="special">)</span> | |
193 | <span class="special">{</span> | |
194 | <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="identifier">i</span><span class="special">-></span><span class="identifier">get</span><span class="special"><</span><span class="identifier">spanish</span><span class="special">>()</span> | |
195 | <span class="special"><<</span> <span class="string">" <---> "</span> | |
196 | <span class="special"><<</span> <span class="identifier">i</span><span class="special">-></span><span class="identifier">get</span><span class="special"><</span><span class="identifier">english</span><span class="special">>()</span> | |
197 | <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> | |
198 | <span class="special">}</span> | |
199 | <span class="special">}</span> | |
200 | <span class="special">}</span> | |
201 | <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span> | |
202 | <span class="special">}</span> | |
203 | </pre> | |
204 | <p> | |
205 | </p> | |
206 | </div> | |
207 | <div class="section boost_bimap_the_tutorial_the_collection_of_relations_type_configuration_parameters"> | |
208 | <div class="titlepage"><div><div><h4 class="title"> | |
209 | <a name="boost_bimap.the_tutorial.the_collection_of_relations_type.configuration_parameters"></a><a class="link" href="the_collection_of_relations_type.html#boost_bimap.the_tutorial.the_collection_of_relations_type.configuration_parameters" title="Configuration parameters">Configuration | |
210 | parameters</a> | |
211 | </h4></div></div></div> | |
212 | <p> | |
213 | Each collection type of relation has different parameters to control its | |
214 | behaviour. For example, in the <code class="computeroutput"><span class="identifier">set_of_relation</span></code> | |
215 | specification, you can pass a Functor type that compares two types. All | |
216 | of the parameters are exactly as in the standard library containers, except | |
217 | for the type, which is set to the bimap relation and the allocator type. | |
218 | To help users in the creation of each functor, the collection type of relation | |
219 | templates takes an mpl lambda expression where the relation type will be | |
220 | evaluated later. A placeholder named <code class="computeroutput"><span class="identifier">_relation</span></code> | |
221 | is available to bimap users. | |
222 | </p> | |
223 | <p> | |
224 | The following table lists the meaning of the parameters for each collection | |
225 | type of relations. | |
226 | </p> | |
227 | <div class="informaltable"><table class="table"> | |
228 | <colgroup> | |
229 | <col> | |
230 | <col> | |
231 | </colgroup> | |
232 | <thead><tr> | |
233 | <th> | |
234 | <p> | |
235 | name | |
236 | </p> | |
237 | </th> | |
238 | <th> | |
239 | <p> | |
240 | Additional Parameters | |
241 | </p> | |
242 | </th> | |
243 | </tr></thead> | |
244 | <tbody> | |
245 | <tr> | |
246 | <td> | |
247 | <p> | |
248 | <code class="computeroutput"><span class="identifier">left_based</span></code> | |
249 | </p> | |
250 | </td> | |
251 | <td> | |
252 | <p> | |
253 | Not a template. | |
254 | </p> | |
255 | </td> | |
256 | </tr> | |
257 | <tr> | |
258 | <td> | |
259 | <p> | |
260 | <code class="computeroutput"><span class="identifier">right_based</span></code> | |
261 | </p> | |
262 | </td> | |
263 | <td> | |
264 | <p> | |
265 | Not a template. | |
266 | </p> | |
267 | </td> | |
268 | </tr> | |
269 | <tr> | |
270 | <td> | |
271 | <p> | |
272 | <code class="computeroutput"><span class="identifier">set_of_relation</span><span class="special"><</span><span class="identifier">KeyComp</span><span class="special">></span></code> | |
273 | </p> | |
274 | <p> | |
275 | <code class="computeroutput"><span class="identifier">multiset_of_relation</span><span class="special"><</span><span class="identifier">KeyComp</span><span class="special">></span></code> | |
276 | </p> | |
277 | </td> | |
278 | <td> | |
279 | <p> | |
280 | <span class="bold"><strong>KeyComp </strong></span> is a Functor that compares | |
281 | two types using less than. By default, the less-than operator | |
282 | is <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">less</span><span class="special"><</span><span class="identifier">_relation</span><span class="special">></span></code>. | |
283 | </p> | |
284 | </td> | |
285 | </tr> | |
286 | <tr> | |
287 | <td> | |
288 | <p> | |
289 | <code class="computeroutput"><span class="identifier">unordered_set_of_relation</span><span class="special"><</span><span class="identifier">HashFunctor</span><span class="special">,</span><span class="identifier">EqualKey</span><span class="special">></span></code> | |
290 | </p> | |
291 | <p> | |
292 | <code class="computeroutput"><span class="identifier">unordered_multiset_of_relation</span><span class="special"><</span><span class="identifier">HashFunctor</span><span class="special">,</span><span class="identifier">EqualKey</span><span class="special">></span></code> | |
293 | </p> | |
294 | </td> | |
295 | <td> | |
296 | <p> | |
297 | <span class="bold"><strong>HashFunctor </strong></span> converts the <code class="computeroutput"><span class="identifier">relation</span></code> into an <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span></code> value. By default it | |
298 | is <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">hash</span><span class="special"><</span><span class="identifier">_relation</span><span class="special">></span></code>. | |
299 | </p> | |
300 | <p> | |
301 | <span class="bold"><strong>EqualKey </strong></span> is a Functor that | |
302 | tests two relations for equality. By default, the equality operator | |
303 | is <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">equal_to</span><span class="special"><</span><span class="identifier">_relation</span><span class="special">></span></code>. | |
304 | </p> | |
305 | </td> | |
306 | </tr> | |
307 | <tr> | |
308 | <td> | |
309 | <p> | |
310 | <code class="computeroutput"><span class="identifier">list_of_relation</span></code> | |
311 | </p> | |
312 | </td> | |
313 | <td> | |
314 | <p> | |
315 | Not a template. | |
316 | </p> | |
317 | </td> | |
318 | </tr> | |
319 | <tr> | |
320 | <td> | |
321 | <p> | |
322 | <code class="computeroutput"><span class="identifier">vector_of_relation</span></code> | |
323 | </p> | |
324 | </td> | |
325 | <td> | |
326 | <p> | |
327 | Not a template. | |
328 | </p> | |
329 | </td> | |
330 | </tr> | |
331 | <tr> | |
332 | <td> | |
333 | <p> | |
334 | <code class="computeroutput"><span class="identifier">unconstrained_set_of_relation</span></code> | |
335 | </p> | |
336 | </td> | |
337 | <td> | |
338 | <p> | |
339 | Not a template. | |
340 | </p> | |
341 | </td> | |
342 | </tr> | |
343 | </tbody> | |
344 | </table></div> | |
345 | </div> | |
346 | <div class="section boost_bimap_the_tutorial_the_collection_of_relations_type_examples"> | |
347 | <div class="titlepage"><div><div><h4 class="title"> | |
348 | <a name="boost_bimap.the_tutorial.the_collection_of_relations_type.examples"></a><a class="link" href="the_collection_of_relations_type.html#boost_bimap.the_tutorial.the_collection_of_relations_type.examples" title="Examples">Examples</a> | |
349 | </h4></div></div></div> | |
350 | <p> | |
351 | Consider this example: | |
352 | </p> | |
353 | <pre class="programlisting"><span class="keyword">template</span><span class="special"><</span> <span class="keyword">class</span> <span class="identifier">Rel</span> <span class="special">></span> | |
354 | <span class="keyword">struct</span> <span class="identifier">RelOrder</span> | |
355 | <span class="special">{</span> | |
356 | <span class="keyword">bool</span> <span class="keyword">operator</span><span class="special">()(</span><span class="identifier">Rel</span> <span class="identifier">ra</span><span class="special">,</span> <span class="identifier">Rel</span> <span class="identifier">rb</span><span class="special">)</span> <span class="keyword">const</span> | |
357 | <span class="special">{</span> | |
358 | <span class="keyword">return</span> <span class="special">(</span><span class="identifier">ra</span><span class="special">.</span><span class="identifier">left</span><span class="special">+</span><span class="identifier">ra</span><span class="special">.</span><span class="identifier">right</span><span class="special">)</span> <span class="special"><</span> <span class="special">(</span><span class="identifier">rb</span><span class="special">.</span><span class="identifier">left</span><span class="special">+</span><span class="identifier">rb</span><span class="special">.</span><span class="identifier">right</span><span class="special">);</span> | |
359 | <span class="special">}</span> | |
360 | <span class="special">};</span> | |
361 | ||
362 | <span class="keyword">typedef</span> <span class="identifier">bimap</span> | |
363 | <span class="special"><</span> | |
364 | <span class="identifier">multiset_of</span><span class="special"><</span> <span class="keyword">int</span> <span class="special">>,</span> | |
365 | <span class="identifier">multiset_of</span><span class="special"><</span> <span class="keyword">int</span> <span class="special">>,</span> | |
366 | <span class="identifier">set_of_relation</span><span class="special"><</span> <span class="identifier">RelOrder</span><span class="special"><</span><span class="identifier">_relation</span><span class="special">></span> <span class="special">></span> | |
367 | ||
368 | <span class="special">></span> <span class="identifier">bimap_type</span><span class="special">;</span> | |
369 | </pre> | |
370 | <p> | |
371 | Here the bimap relation view is ordered using the information of both sides. | |
372 | This container will only allow unique relations because <code class="computeroutput"><span class="identifier">set_of_relation</span></code> | |
373 | has been used but the elements in each side of the bimap can be repeated. | |
374 | </p> | |
375 | <pre class="programlisting"><span class="keyword">struct</span> <span class="identifier">name</span> <span class="special">{};</span> | |
376 | <span class="keyword">struct</span> <span class="identifier">phone_number</span> <span class="special">{};</span> | |
377 | ||
378 | <span class="keyword">typedef</span> <span class="identifier">bimap</span> | |
379 | <span class="special"><</span> | |
380 | <span class="identifier">tagged</span><span class="special"><</span> <span class="identifier">unordered_multiset_of</span><span class="special"><</span> <span class="identifier">string</span> <span class="special">>,</span> <span class="identifier">name</span> <span class="special">>,</span> | |
381 | <span class="identifier">tagged</span><span class="special"><</span> <span class="identifier">unordered_set_of</span> <span class="special"><</span> <span class="keyword">int</span> <span class="special">>,</span> <span class="identifier">phone_number</span> <span class="special">>,</span> | |
382 | <span class="identifier">set_of_relation</span><span class="special"><></span> | |
383 | ||
384 | <span class="special">></span> <span class="identifier">bimap_type</span><span class="special">;</span> | |
385 | </pre> | |
386 | <p> | |
387 | In this other case the bimap will relate names to phone numbers. Names | |
388 | can be repeated and phone numbers are unique. You can perform quick searches | |
389 | by name or phone number and the container can be viewed ordered using the | |
390 | relation view. | |
391 | </p> | |
392 | </div> | |
393 | </div> | |
394 | <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> | |
395 | <td align="left"></td> | |
396 | <td align="right"><div class="copyright-footer">Copyright © 2006-2012 Matias Capeletto<p> | |
397 | Distributed under the Boost Software License, Version 1.0. (See accompanying | |
398 | file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>) | |
399 | </p> | |
400 | </div></td> | |
401 | </tr></table> | |
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